textproduct: Quad Cities

KEY MESSAGES

- There is an Enhanced Risk/Level 3 of 5 for severe weather for our southwest counties, with damaging wind the primary risk in the evening hours, but all modes of severe weather possible. Lower risks of 1,2 are found northeast through the rest of the area. - Cooler and drying out this weekend, with sub freezing lows expected Monday night.

- Another widespread rainfall event is gaining confidence for late this week.

SHORT TERM /THROUGH TONIGHT/

Issued at 221 AM CDT Fri Apr 3 2026

Today is yet another challenging day of Spring forecasting!

Cold advection with cyclonic moist flow in the wake of last night's storm system has brought extensive stratus to the Cornbelt states. However, the wavelength between last night's storm system and the next one up is very very short, and we are already seeing increasing LLJ moisture feed into the western Plains. For now, this has resulted in rain spreading through northern Nebraska and western South Dakota as of 2 AM. This LLJ is forecast to veer into Iowa today, and result in new showers and storms in western Iowa by this morning. These are not expected to be strong initially, but will potentially move into eastern Iowa by late morning. This activity will certainly have potential to persist into the afternoon hours, mainly in the northwest CWA. The main impact of that activity will be to hold down highs to the 50s today, and set up yet another sharp frontal boundary near I-80 for the evening hours, as the southern CWA reaches the low 70s today.

The severe risk late this afternoon and this evening continues to be supported by a strong upper level low pressure passing through the upper midwest, resulting in increasing deep layer shear profiles through the afternoon. By early evening, an intensifying LLJ around 50kts a few thousand feet up will greatly increase coverage of storms within our CWA, especially eastern Iowa and western Illinois, north of Highway 34. PWAT values of 1.25 to 1.50 will support heavy rain amounts within this line, but quick 40-50 mph storm motions will keep amounts low outside of where the line alignment allows for some training storms. This is most likely in eastern Iowa, where amounts over 1 inch are expected to fall between I-80 and Highway 20, with lower chances farther east and south.

Questionable heating and a somewhat muddy convective picture at mid day suggest this forecast is prone to a lower end than yesterday's supercells with very large hail and tornadoes. However, with the strong evening shear, tornadoes, large hail, and damaging winds are possible, especially in eastern Iowa through Midnight, and in any discreet storms found near the warm front this afternoon, which could be stalled between I-80 and Highway 34.

By late evening, an progressive line will continue eastward through Illinois, losing instability as it moves east, while maintaining a fast movement. Thus QPF should greatly diminish, with some wind threat remaining until the line exits our CWA in the early morning hours.

LONG TERM /SATURDAY THROUGH THURSDAY/

Issued at 221 AM CDT Fri Apr 3 2026

Saturday will see conditions begin to dry out and turn cooler as high pressure begins to build in.

Sunday-Tuesday...Continued cooler and more seasonable this stretch into early next week, with a return flow induced precip event possible some time Tue into next Wed. There will also be a concern for frost/freeze potential especially Mon night/Tue AM due to recent greenup that will need to be evaluated in later forecasts.

The signal for southwest flow aloft, and yet another broad moist warm advection rain event is gaining support in all extended guidance and ensemble data for the Thursday - Friday time period. Once again, QPF may be support of an above normal period in the next 7 days. It seems like our drought recovery is going along nicely in most areas now!

AVIATION /12Z TAFS THROUGH 12Z SATURDAY/

Issued at 559 AM CDT Fri Apr 3 2026

Active aviation forecast ahead of us, as another storm system approaches the area today. Starting off the TAF period, we will remain under an MVFR stratus deck between 1000-1500 ft. As we approach 18z, some sites will see cigs increase a little, but should largely remain MVFR. After 18z, we will see our best chance of some breaks in the clouds along/south of Interstate 80. Thus, we might see some brief improvements at BRL and MLI. Otherwise, between 00-06z we will see our next round of thunderstorms move through the area from west-east. We can expect reductions in vis and cigs as this passes through. Uncertainly in timing remains. Thus, we opted to hold onto the PROB30 group for this forecast.

Aside from the shower and storm potential, winds will be quite variable to start the day, trending more easterly by 15-18z throughout. After 18z, we will see winds pick up out of the south-southeast, as the surface low tracks near. Winds will generally remain between 10-15 KTs, with gusts upwards to 20 KTs. After 00z, the surface low will track through the area, resulting in quite variable and gusty winds. We can see gusts upwards to 25 KTs prior to the low passing over the area, especially at DBQ and CID, and then again on the backside from the west.

DVN WATCHES/WARNINGS/ADVISORIES

IA...None. IL...None. MO...None.